Tuesday, March 20, 2018

New Leaves of the Mockernut Hickory (Carya tomentosa)

The mockernut hickory (Carya tomentosa) has very large end buds. This end bud is at minimum an inch in length. The new leaves are still hidden.
This end bud has started to open: the velvety outer layer is peeling back.
The young, furry, compound leaves are revealed.

Big-Leaf Magnolia Leaf Bud

This is the top of a big-leaf magnolia tree (Magnolia macrophylla). The tree is still young, so it has the appearance of simply being a stick, stuck in the ground, but then at the top of the stick, there is a very large, velvety, whitish end bud, not quite opening.

First Day of Spring

The vernal equinox is today, marking the first day of spring, so we are celebrating with a few pictures of springtime flowers!

Devilwood (Osmanthus americanus)
Flowering Dogwood (Cornus florida)
Louisiana Iris Hybrids
Zig-zag Louisiana Iris (Iris brevicaulis)

Sunday, March 18, 2018

Tree of the Week: Devilwood (Osmanthus americanus)

The devilwood (Osmanthus americanus) is blooming this week, and the flowers provide the opportunity for a pleasurable olfactory experience. The devilwood is a small, slender tree that keeps a low-profile. Unlike the numerous, bright, white flowers of the Mexican plum that we discussed last week, the devilwood's flowers are inconspicuous. So, in order to appreciate their splendid aroma, you will need to seek it out. Pictures are provided below to help you locate it!

There is only one devilwood in the arboretum. It's located west of Mickle Hall, down the slope, below the sidewalk and next to the gravel path. Ed Leuck collected this specimen in March of 1985, from the Caroline Dormon Nature Preserve in rural Bienville Parish. At over 30 years old, the tree is healthy, but due to tough competition, it isn't thriving.

The devilwood tree is pictured center with Mickle Hall in the background. It is over 30 years old. The trunk is slender and the drooping branches are light and elegant.
Over the years the devilwood has developed a considerable lean in its trunk, bending eastward toward the sidewalk, away from all of the shade cast by the southern sugar maple. The devilwood and the maple were actually collected in the same year, 1985, but the maple quickly grew up and out, crowding out the devilwood, gobbling up all of the sun rays.
The elegant branches have evergreen leaves and small clusters of white flowers. 
These tiny white flowers have a delightful fragrance of modest potency.
The simple evergreen leaves have a lanceolate shape, coming to a point at the tip. They have a dark green waxy upper surface and a pale green lower surface. The leaf edges are smooth.
The leaves are long and thin, measuring up to 4 or 5 inches in length.

You can find more images of the arboretum's devilwood here.

For more information about this species consult the following online sources:
United States Department of Agriculture
University of Florida IFAS
NC State University
Louisiana Plant Identification and Interactive Virtual Tours (LSU AgCenter)

Sunday, March 11, 2018

Springtime Flowers

New Leaves

Ashe's viburnum (Viburnum ashei)
Arrow wood viburnum (Viburnum dentatum)
Toothache tree (Zanthoxylum clava-herculis)

Tree of the Week: Mexican Plum (Prunus mexicana)

Pretty springtime flowers can be found throughout the arboretum. The redbud trees, atamasco lilies and butterweed are just a few of the colorful notes in the landscape. The Mexican plum (Prunus mexicana) is especially noticeable this week. Its flowers are bright white.

There are more than five Mexican plums in the arboretum collection. You can find them in three different locations. The tree pictured below is near the Fitness Center. It's a volunteer that we first noticed in 2006, which means that it is at minimum 12 years old.  
The bright white flowers stand out in the landscape. And since most of the deciduous trees are still leafless, you can see the blooming Mexican plum from quite a distance.

The Mexican plum volunteered near the drainage channel over 12 years ago. It's origins are unknown. Two sweet bay magnolias were planted near the concrete bridge, a couple of years prior to the identification of the Mexican plum, so the plum was simply added to grouping. The sweet bays are growing vertically, while the plum is stretching out horizontally.
The Mexican plum is doing marvelously in this low spot. The other Mexican plums are located higher up, on the slopes of the arboretum.
An up-close inspection of the flower clusters reveals that each flower has a crimson center. The flowers are fragrant, but not as fine as the crabapple.
The short twisting trunk divides into three large branches.
Mexican plums have dark, rough, peeling bark that adds to their beauty throughout the year. The swamp leather-flower (Clematis crispa) is using the rough bark as a trellis.

You can see photos of the arboretum's other Mexican plums here.